Lapping and grinding machine



June 30, 1925. 1,543,974

H E. BARNES LAPPING AND GRINDING MACHINE Filed July 1'7, 1923 2Sheets-Sheet 1 June 30, 1925.

1,543,974 H. E. BARNES Y LAPPING AND GRINDING MACHINE Y Filed July 1'7,1923 2 Sheets-Sheet 2 (I W m Patented June 30, 1925.

- UNITED STATES PATENT @FFICE.

HERMAN n. BARNES, or nous'ron, TEXAS.

LAPPING AND GRINDING MACHINE.

Application filed July 17, 1923. Serial 1%. 652,051.

of Texas, have invented certain new and useful Improvements in Lappingand Grinding Machines, of which the following is a specification.

This invention relates to certain new and useful improvements in alapping and grinding machine.

One object of the invention is to provide a machine of the characterdescribed specially designed for lapping or grinding the ball joints oflocomotive super-heater units so as to give said joints a perfectlysmooth oval surface. The machine, however, may be used for any analogouspurpose.

Another object of the invention is to provide a machine of the characterdescribed, so designed thatwhen set in motion its action will beautomatic, and any desired number of said joints may be operated on atthe same time.

A further feature resides in the provision V of a machine of thischaracter which is very simple in construction and consequently may becheaply and easily constructed and kept in repair.

TVith the above and other objects in view, this invention has particularrelation to certain novel features of construction, opera tion andarrangement of parts, an example of which is given in this specificationand illustrated in the accompanying drawings wherein Figure 1 shows afront elevation of the machine.

Figure 2 shows aside view.

Figure 3 shows a plan view of the grinder head and spindle.

Figure ishows a side view of the spindle connected to the head, thelatter being shown in section, and,

Figure 5 shows a transverse sectional view of the head, taken on theline 5-5 of Figure 4:,

In the drawings the numeral 1 refers to the stand which has a bracket,as 2, fastened to the front side and provided to hold one or more of thetubular super-heater units, as 3, clamped in position to be operatedupon. Each unit has a ball joint 4 at one end which must be lapped, orground to a very smooth surface, for the reason well known to thosefamiliar with the art of locomotive boiler construction. Rotatablymounted in suitable vertically aligned bearings, carried by the stand,there is one or more vertical shafts, as 5. If more than one shaft 5 isemployed these shafts have the spur gears, as 6, keyed thereon, and inmesh with an intermediate gear 7. The lower end of each shaft 6 carriesa chuck, as 8, provided to receive the spindle 9, which is operativelyconnected with, and driven by said chuck. The numeral 10 designates thegrinder head which may be formed in sections clamped together by a clampring 11. The head has the insert 12, preferably of lead and formed witha socket of the contour of the ball joint desired. The lower end of thespindle has an eccentric ball joint 13 which works in a socket 1 1 ofthe head against suitable anti-friction bearings, as 15, therein.

The ball joint to be ground is seated in the socket of the lead insert12, said socket having been previously lubricated and supplied with afine abrasive powder The machineis then started and as the spindle 9rotates, it will impart a uniform gyratory motion to the head and theball joint 41 will be ground to a smooth and uniform oval contour.

The driving mechanism includes a counter shaft 16 mounted to rotate insuitable bear ings carried by the stand and fixed upon one end of whichis a drive pulley 17. This shaft has a pinion 18 fixed thereon and inmesh with a similar pinion 19 which is fixed on the upper end of thestub shaft whose lower end carries the spur gear 20. This gear 20 is inmesh with, and drives a similar spur gear 21 which is loosely mounted onone of the shafts 5, and which is formed with a clutch member capable ofbeing clutched with and declutched from the clutch 22, splined on saidshaft. This clutch may be manipulated in the usual way through themanipulating lever 23 to connect said shaft 5 with, or disconnect itfrom the driving mechanism.

A. tension lever 23 is provided for each drive shaft 5, each lever beingpivoted to the upper end of a corresponding standard 24:. There is astrong coil spring 25 for each lever, one end of said spring beinganchored to the stand and its other end being attached to one end of thecorresponding lever. The other end of each lever carries a suitableweight 26 and between said weight and the pivotal mounting of the leverthere is a bracket 27, pivoted to said lever and with which thecorresponding shaft 5, has a swivelling connection. The weights exert anendwise pressure through the shafts 5 to the heads 10, thus holding themyieldingly but firmly against the Work.

In the construction of my machine I have taken advantage of the factthat the spherical metallic surface to be ground can be made to act=uponitself in aiding the grinding ope "ation. The simplicity of thisconstruction is readily apparent because a single grinding'cup or headonly is necessary, the spherical partto be ground serving in reality asthe lower grinding head.

In operation the spherical metallic surface or, head, such as theballjoint of a locomotive superheater union connection where it joins themain steam header, is releasably secured in my machine against movement,then the universally movable grinding cup propelled by the crankconnected to the main drive shaft is'brought into contact with themetallic surface.

In effect during the. grinding operation the rotation of the drive shaftpropels the cup in circular movement around the axis of the sphericalhead, and the spherical head guides the cup over its own sphericalcontour. This scope movement of the grinding cup over the sphericalmetallic surface prevents ring cutting or grooving, which commonlyoccurs where lapping oii'grinding is done where the lap or grinding headtravels over the work in a constant path; this being due to thegroundoif metallic particles being carried around continuously in thesame path. By iny improved construction the sweeping effect of thegrinding head over the spherical metallic surface clears the grindingabrasive with themetallic particles therein over the outer circumferenceof the part to waste, rendering itposslble to effect contmuous grinding1n a power operated machine without ring cutting, thereby expediting thegrinding time and permitting even unskilled help to operate theapparatus while producing. a ground into fluid tight engagement withoutleale T It is further desired to bring out the fact in-my improvedmachine that through the automatic clearance effect of the grindingabrasive with its offensive metallic particles, by reason of the scopemovement of the grinding cup in the circular movement of the cup aroundtheaxis of the spherical surface being ground, that it is possible forthe operator to completely finish the grinding of thesurface withoutstoppage of the macnine, it only being necessary to raise the revolvinggrinding cup occasionally from its encompassing engagement with thespherical surface, and then only momentarily in order to apply newabrasive with a swab orv brush.

ground, with the axis of said head axially in line with said shaft, acrank on the end of said shaft and a cup having an hemispherical,internalor concave surface, the counterpart of that desired to beformed, mounted loosely by a universal joint upon the free end of saidcrank and adapted to be engaged and be guided by said article and causedto have a free rotary motion about an axis of the cup intersecting saidjoint, as well a gyratory motion of said axis produced by the crank, theradius of the crank and the angle of the axis of the cup being suchthatthe edge of the cup constantly intersects a diameter of the head atright angles to the common axis of the work and the shaft.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

HERMAN E. BARNES.

Vvitnesses W. H. DUNLAY, WM. A. CATHEY.

